Many of the existing electronic devices (e.g. portable notebook computer, smart phone, tablet computer, etc.) have a projection function. However, this projection function can be used conveniently only when the electronic device is in some specific usage state (also referred as a usage mode). This specific usage state requires the electronic device to keep in a certain posture, and if the electronic device changes to another posture, the screen projected by the projector might be deflected so that the user cannot conveniently watch the projection screen.
An electronic device such as a tablet computer usually has its own bracket which, when opened by the user, supports the standing-up mode of the tablet computer. The back-mounted camera of the tablet computer is usually installed near the location of the bracket. With the improvement of the quality of the camera, the field of view (FOV) of the camera enlarges more and more. In case the bracket is opened, it usually appears in the FOV scope of the camera and affects the image effect, and thus causes a worse user experience.